U.S. health-policy proposals under the Trump administration and Health Secretary Robert F. Kennedy Jr. are prompting vaccine manufacturers to raise concerns about rapid, wide-ranging changes to childhood immunization policy. STAT reported that officials are considering discouraging or banning common vaccine adjuvants and splitting combination vaccines — moves that could force manufacturers to redevelop formulations, a process that can take a decade and cost upwards of $1 billion. Industry sources warn the changes could reduce availability of established pediatric vaccines and risk erosion of protection against measles, mumps, rubella, pertussis, polio and other diseases. The reporting cites interviews with vaccine-company employees and federal policy documents reviewed by STAT. Manufacturers say alternative development timelines and costs would strain supply and delay access. The story also notes recent political shifts at HHS and changes to advisory panels, which provide the regulatory and public-health context for the proposals.